WASHINGTON – House Ways and Means Chairman Richard Neal escalated the fight over President Donald Trump's tax returns Friday afternoon when he issued subpoenas for the documents to Department of Treasury Secretary Steven Mnuchin and Internal Revenue Service (IRS) Commissioner Charles Rettig.

The Treasury Department had previously rejected Neal's request for six years of the president's tax returns.

"While I do not take this step lightly, I believe this action gives us the best opportunity to succeed and obtain the requested material," Neal said in a statement. "I sincerely hope that the Treasury Department will furnish the requested material in the next week so the committee can quickly begin its work.”

"In reliance on the advice of the Department of Justice, I have determined that the Committee's request lacks a legitimate legislative purpose, and pursuant to section 6103, the Department is therefore not authorized to disclose the requested returns and return information," Mnuchin wrote.

Neal made the original request for Trump's 2013-2018 tax returns to the IRS, which is part of the Treasury Department. He invoked a law allowing a select few members of Congress to review individual tax returns for legislative purposes and cited legislative proposals and oversight related to federal tax laws as his basis for the request.

It was the first such demand for a sitting president’s tax information in 45 years.

Neal also demanded copies of tax returns for Trump's trust and for his golf club in Bedminster, New Jersey.

The subpoena comes as part of a broader effort from Congress to obtain documents and bring administration officials and allies in for questioning.

Earlier that day, Democrats on the House Judiciary Committee voted to hold Attorney General William Barr in contempt of Congress over his refusal to hand over an unredacted copy of Special Counsel Robert Mueller's report on the Russian interference in the 2016 election.